<?php

/**
 * @file
 * Admin page callbacks for the book module.
 */

/**
 * Returns an administrative overview of all books.
 */
function book_admin_overview() {
	$rows = array();

	$headers = array(t('Book'), t('Operations'));

	// Add any recognized books to the table list.
	foreach (book_get_books() as $book) {
		$rows[] = array(l($book['title'], $book['href'], $book['options']), l(t('edit order and titles'), 'admin/content/book/' . $book['nid']));
	}

	return theme('table', array('header' => $headers, 'rows' => $rows, 'empty' => t('No books available.')));
}

/**
 * Builds and returns the book settings form.
 *
 * @see book_admin_settings_validate()
 *
 * @ingroup forms
 */
function book_admin_settings() {
	$types = node_type_get_names();
	$form['book_allowed_types'] = array(
			'#type' => 'checkboxes',
			'#title' => t('Content types allowed in book outlines'),
			'#default_value' => variable_get('book_allowed_types', array('book')),
			'#options' => $types,
			'#description' => t('Users with the %outline-perm permission can add all content types.', array('%outline-perm' => t('Administer book outlines'))),
			'#required' => TRUE,
	);
	$form['book_child_type'] = array(
			'#type' => 'radios',
			'#title' => t('Content type for child pages'),
			'#default_value' => variable_get('book_child_type', 'book'),
			'#options' => $types,
			'#required' => TRUE,
	);
	$form['array_filter'] = array('#type' => 'value', '#value' => TRUE);
	$form['#validate'][] = 'book_admin_settings_validate';

	return system_settings_form($form);
}

/**
 * Validate the book settings form.
 *
 * @see book_admin_settings()
 */
function book_admin_settings_validate($form, &$form_state) {
	$child_type = $form_state['values']['book_child_type'];
	if (empty($form_state['values']['book_allowed_types'][$child_type])) {
		form_set_error('book_child_type', t('The content type for the %add-child link must be one of those selected as an allowed book outline type.', array('%add-child' => t('Add child page'))));
	}
}

/**
 * Build the form to administrate the hierarchy of a single book.
 *
 * @see book_admin_edit_submit()
 *
 * @ingroup forms.
 */
function book_admin_edit($form, $form_state, $node) {
	drupal_set_title($node->title);
	$form['#node'] = $node;
	_book_admin_table($node, $form);
	$form['save'] = array(
			'#type' => 'submit',
			'#value' => t('Save book pages'),
	);

	return $form;
}

/**
 * Check that the book has not been changed while using the form.
 *
 * @see book_admin_edit()
 */
function book_admin_edit_validate($form, &$form_state) {
	if ($form_state['values']['tree_hash'] != $form_state['values']['tree_current_hash']) {
		form_set_error('', t('This book has been modified by another user, the changes could not be saved.'));
	}
}

/**
 * Handle submission of the book administrative page form.
 *
 * This function takes care to save parent menu items before their children.
 * Saving menu items in the incorrect order can break the menu tree.
 *
 * @see book_admin_edit()
 * @see menu_overview_form_submit()
 */
function book_admin_edit_submit($form, &$form_state) {
	// Save elements in the same order as defined in post rather than the form.
	// This ensures parents are updated before their children, preventing orphans.
	$order = array_flip(array_keys($form_state['input']['table']));
	$form['table'] = array_merge($order, $form['table']);

	foreach (element_children($form['table']) as $key) {
		if ($form['table'][$key]['#item']) {
			$row = $form['table'][$key];
			$values = $form_state['values']['table'][$key];

			// Update menu item if moved.
			if ($row['plid']['#default_value'] != $values['plid'] || $row['weight']['#default_value'] != $values['weight']) {
				$row['#item']['plid'] = $values['plid'];
				$row['#item']['weight'] = $values['weight'];
				menu_link_save($row['#item']);
			}

			// Update the title if changed.
			if ($row['title']['#default_value'] != $values['title']) {
				$node = node_load($values['nid']);
				$langcode = LANGUAGE_NONE;
				$node->title = $values['title'];
				$node->book['link_title'] = $values['title'];
				$node->revision = 1;
				$node->log = t('Title changed from %original to %current.', array('%original' => $node->title, '%current' => $values['title']));

				node_save($node);
				watchdog('content', 'book: updated %title.', array('%title' => $node->title), WATCHDOG_NOTICE, l(t('view'), 'node/' . $node->nid));
			}
		}
	}

	drupal_set_message(t('Updated book %title.', array('%title' => $form['#node']->title)));
}

/**
 * Build the table portion of the form for the book administration page.
 *
 * @see book_admin_edit()
 */
function _book_admin_table($node, &$form) {
	$form['table'] = array(
			'#theme' => 'book_admin_table',
			'#tree' => TRUE,
	);

	$tree = book_menu_subtree_data($node->book);
	$tree = array_shift($tree); // Do not include the book item itself.
	if ($tree['below']) {
		$hash = drupal_hash_base64(serialize($tree['below']));
		// Store the hash value as a hidden form element so that we can detect
		// if another user changed the book hierarchy.
		$form['tree_hash'] = array(
				'#type' => 'hidden',
				'#default_value' => $hash,
		);
		$form['tree_current_hash'] = array(
				'#type' => 'value',
				'#value' => $hash,
		);
		_book_admin_table_tree($tree['below'], $form['table']);
	}

}

/**
 * Recursive helper to build the main table in the book administration page form.
 *
 * @see book_admin_edit()
 */
function _book_admin_table_tree($tree, &$form) {
	// The delta must be big enough to give each node a distinct value.
	$count = count($tree);
	$delta = ($count < 30) ? 15 : intval($count / 2) + 1;

	foreach ($tree as $data) {
		$form['book-admin-' . $data['link']['nid']] = array(
				'#item' => $data['link'],
				'nid' => array('#type' => 'value', '#value' => $data['link']['nid']),
				'depth' => array('#type' => 'value', '#value' => $data['link']['depth']),
				'href' => array('#type' => 'value', '#value' => $data['link']['href']),
				'title' => array(
						'#type' => 'textfield',
						'#default_value' => $data['link']['link_title'],
						'#maxlength' => 255,
						'#size' => 40,
				),
				'weight' => array(
						'#type' => 'weight',
						'#default_value' => $data['link']['weight'],
						'#delta' => max($delta, abs($data['link']['weight'])),
						'#title' => t('Weight for @title', array('@title' => $data['link']['title'])),
						'#title_display' => 'invisible',
				),
				'plid' => array(
						'#type' => 'hidden',
						'#default_value' => $data['link']['plid'],
				),
				'mlid' => array(
						'#type' => 'hidden',
						'#default_value' => $data['link']['mlid'],
				),
		);
		if ($data['below']) {
			_book_admin_table_tree($data['below'], $form);
		}
	}

	return $form;
}

/**
 * Returns HTML for a book administration form.
 *
 * @param $variables
 *   An associative array containing:
 *   - form: A render element representing the form.
 *
 * @see book_admin_table()
 * @ingroup themeable
 */
function theme_book_admin_table($variables) {
	$form = $variables['form'];

	drupal_add_tabledrag('book-outline', 'match', 'parent', 'book-plid', 'book-plid', 'book-mlid', TRUE, MENU_MAX_DEPTH - 2);
	drupal_add_tabledrag('book-outline', 'order', 'sibling', 'book-weight');

	$header = array(t('Title'), t('Weight'), t('Parent'), array('data' => t('Operations'), 'colspan' => '3'));

	$rows = array();
	$destination = drupal_get_destination();
	$access = user_access('administer nodes');
	foreach (element_children($form) as $key) {
		$nid = $form[$key]['nid']['#value'];
		$href = $form[$key]['href']['#value'];

		// Add special classes to be used with tabledrag.js.
		$form[$key]['plid']['#attributes']['class'] = array('book-plid');
		$form[$key]['mlid']['#attributes']['class'] = array('book-mlid');
		$form[$key]['weight']['#attributes']['class'] = array('book-weight');

		$data = array(
				theme('indentation', array('size' => $form[$key]['depth']['#value'] - 2)) . drupal_render($form[$key]['title']),
				drupal_render($form[$key]['weight']),
				drupal_render($form[$key]['plid']) . drupal_render($form[$key]['mlid']),
				l(t('view'), $href),
				$access ? l(t('edit'), 'node/' . $nid . '/edit', array('query' => $destination)) : '&nbsp;',
				$access ? l(t('delete'), 'node/' . $nid . '/delete', array('query' => $destination) )  : '&nbsp;',
		);
		$row = array('data' => $data);
		if (isset($form[$key]['#attributes'])) {
			$row = array_merge($row, $form[$key]['#attributes']);
		}
		$row['class'][] = 'draggable';
		$rows[] = $row;
	}

	return theme('table', array('header' => $header, 'rows' => $rows, 'attributes' => array('id' => 'book-outline')));
}
